1. Field of the Invention
Embodiments of the present invention relate to an apparatus and method that may analyze a position of a mobile node and a received signal strength of packet data using packet data received from the mobile node, and may track a position of a fixed node based on the analysis result.
2. Description of the Related Art
In general, a node of which a position is to be tracked (hereinafter, an unknown node) in a wireless network may predict a distance from a reference node and may predict the position of the unknown node based on the predicted distance.
A distance prediction scheme may include a Time of Arrival (TOA) scheme for measuring a travel time of an ultrasonic signal, a Time Difference of Arrival (TDOA) scheme using a time difference of arrival between two signals of which speeds are different from each other, and a Received Signal Strength Indicator (RSSI) scheme using a signal strength.
However, the TOA scheme and the TDOA scheme may require additional hardware for distance measurement or a high performance sight measurement apparatus. Also, in the case of the RSSI scheme, a distance prediction may be inaccurate due to a change in the signal strength according to an environment, a different antenna pattern according to a direction, an obstacle, and the like. In addition, to employ the RSSI scheme, a plurality of reference nodes being aware of their own positions may need to be arranged in a network arrangement area. In general, an installer may directly input the positions of the reference nodes, thereby increasing an arrangement cost and an arrangement time in the substantial arrangement.
Accordingly, there is a need for technology that may track positions of a plurality of reference nodes and also decrease an arrangement cost of a network without using additional hardware.